A Boundary and Texture Preserving Mesh Simplification Algorithm for Virtual Reality

Abstract

With the increasing accessibility of the mobile head-mounted displays (HMDs), mobile virtual reality (VR) systems are finding applications in various areas. However, mobile HMDs are highly constrained with limited graphics processing units (GPUs), low processing power and onboard memory. Hence, VR developers must be cognizant of the number of polygons contained within their virtual environments to avoid rendering at low frame rates and inducing simulator sickness. The most robust and rapid approach to keeping the overall number of polygons low is to use mesh simplification algorithms to create low-poly versions of preexisting, high-poly models. Unfortunately, most existing mesh simplification algorithms cannot adequately handle meshes with lots of boundaries or non-manifold meshes, which are common attributes of 3D models made with computer-aided design tools.; AB@In this paper, we present a high-fidelity mesh simplification algorithm specifically designed for VR. This new algorithm, QEM4VR, addresses the deficiencies of prior quadric error metric (QEM) approaches by leveraging the insight that the most relevant boundary edges lie along curvatures while linear boundary edges can be collapsed. Additionally, our QEM4VR algorithm preserves key surface properties, such as normals, texture coordinates, colors, and materials. It pre-processes the 3D models and generate their low-poly approximations offline. We used six publicly available, high-poly models, with and without textures to compare the accuracy and fidelity of our QEM4VR algorithm to previous QEM variations. We also performed a frame rate analysis with original high-poly models and low-poly models obtained using QEM4VR and previous QEM variations. Our results indicate that QEM4VR creates low-poly, high-fidelity virtual environments for VR applications on devices that are constrained by the low number of polygons they can work with.